INFECTION BY MILK 99 



ease is accompanied by fever and signs of great consti- 

 tutional disturbance, and it quite often ends in death. 

 The pathological changes have been studied compara- 

 tively little up to this time. It may, however, be stated 

 that there 'is sometimes found a diffuse inflammatory 

 hypersemia in the mucous membrane of the whole small 

 intestine, sometimes very extensive pseudo-membranes 

 form a cast within the intestine, while in other cases 

 swelling and hemorrhagic infiltration of Peyer's patches 

 are found which, at the same time, may be ulcerated, or 

 covered with crupo-diphtheritic exudate. The mesen- 

 teric glands, usually other glands, too, are swollen and 

 more or less hyperaemic, or even hemorrhagic ; the spleen 

 may be enormously swollen. In some cases the lesions 

 somewhat resemble typhoid fever in man, yet the disease 

 is not identical with it. 



The investigations that have been made by Jensen 

 indicate that these forms of enteritis are, as a rule, 

 caused by bacteria which belong to the hog cholera group 

 and that are therefore closely related to the typhoid 

 bacillus. The flesh of the infected animals may be most 

 dangerous to health; not a few of the so-called " meat 

 poisoning," epidemics have been traced directly to these 

 forms of enteritis, and most of the bacteria isolated in 

 meat poisoning cases belong to the hog cholera group. 



It is not impossible that in virulent enteritis bacteria 

 that have entered the blood may, now and then, be 

 excreted in the milk as, for example, when there are 

 slight hemorrhages in the udder tissue; doubtless, 

 however, a serious contamination may occur during 

 milking, for in this disease diarrhoea is a prominent 

 symptom and the afflicted animals are much soiled by 

 their faeces. 



A positive example of the transmission of such a 

 form of enteritis to man through milk, has been given 



